Использование loop.php в дочерних темах

will do a PHP require() for the first file that exists among these, in this priority:

wp-content/themes/twentytenchild/loop-index.php

wp-content/themes/twentyten/loop-index.php

wp-content/themes/twentytenchild/loop.php

wp-content/themes/twentyten/loop.php

Using with theme subfolders

To use this function with subfolders in your theme directory, simply prepend the folder name before the slug. For example, if you have a folder called "partials" in your theme directory and a template part called "content-page.php" in that sub-folder, you would use get_template_part() like this:

<?php get_template_part( 'partials/content', 'page' ); ?>

Навигация

Adding a navigation bar to theme using a generic nav.php template file: